What is Ghost Cleanup Task in Sql Server?

Ans: When you delete a row, SQL Server does not physically remove the row from the page. Rather, it flags deleted rows as ghosted (deleted) in the status bits. This speeds up deletion and allows SQL Server to undo it quickly if necessary.
The deletion process also sets a flag in the PFS(Page Free Space) page indicating that there is a ghosted row on the page. SQL Server removes ghosted rows in background through a task called the ghost cleanup task.

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